Big Mighty-can't comment on plasmapheresis as we haven't done that, but agree with dcmom--as long as he feels ok, go for it. Some schools will actually refund tuition for medical withdrawal (depends on the school), and if he works closely with the school's disability support office, they can help with everything from preferential course selection times and accommodations in classroom to placing him in a good residence hall health-wise (A/C, no dust or mold, etc.) with a carefully chosen RA and whatever roommate situation (single, double, triple, etc) would best support him. If he has a good roommate, that may also be someone who can be an extra line of communication if he feels ok opening up about the PANDAS stuff. I had several college friends (way, way back in the day, haha!) whose parents communicated often and closely with their roommates to help monitor stuff like eating disorders and mental health. So agree it can be done, just carefully....again, sorry not to be much help about your main question but hope that you are able to get some good answers on that as well. PS-I don't know from your description if your son actually uses stuff like testing accommodations now, but absolutely make sure he puts them in place next year--much better to have and not use, than the reverse!